1. Field of the Invention
The present invention relates to a display panel, and more particularly to a liquid crystal display (LCD) panel.
2. Description of Related Art
Display viewing angles of LCDs are required to be increasing largely in the market. Currently, the common wide viewing angle technology is multi-domain vertical alignment LCD panel, which adopts an alignment structure to make liquid crystal molecules in different regions to tilt along different directions, thereby achieving the effect of wide viewing angle. However, the disclination of liquid crystal molecules on the periphery of the alignment structure often occurs, resulting in the light leakage. Therefore, an alignment manner of polymer-stabilized alignment (PSA) together with a pixel electrode having a plurality of micro slits to form multi-domain alignment is proposed to solve the problem of the poor display effect of the multi-domain vertical alignment LCD panel.
FIG. 1 shows a pixel structure of the polymer-stabilized alignment LCD panel (PSA-LCD) in the prior art. Referring to FIG. 1, a pixel structure 100 is electrically connected with the scan lines 102 and data lines 104, and the pixel structure 100 includes a first active device 106, a second active device 108, a first pixel electrode 110, and a second pixel electrode 120. The first active device 106 and the second active device 108 are electrically connected to the first pixel electrode 110 and the second pixel electrode 120 respectively. The first pixel electrode 110 and the second pixel electrode 120 are spaced by a main slit 130, such that the first pixel electrode 110 and the second pixel electrode 120 may have different display voltages. Furthermore, the first pixel electrode 110 has a plurality of fine slits 112, and the second pixel electrode 120 has a plurality of fine slits 122.
The disposition of fine slits 112 and 122 makes the liquid crystal molecules tilt along different directions, so as to exhibit a display effect of wide viewing angle. In the orientation of reference coordinate C, the pixel structures 100 is preferably designed to make the liquid crystal molecules located above the first pixel electrode 110 and the second pixel electrode 120 tilt along the directions of 45°, 135°, 225°, and 315°, so as to achieve an optimal display effect. However, the liquid crystal molecules located above the main slit 130 tilt along the directions of 90° and 270°, thus adversely affecting the display effect of the pixel structures 100. The simulation results show that when viewing at a large viewing angle in the horizontal direction, the tilting of liquid crystal molecules along the directions of 90° and 270° may improve the medium and low gray-scale display brightness and decrease the high gray-scale display brightness. Therefore, the tilting of the liquid crystal molecules along the directions of 90° and 270° may aggravate the color washout and the color shift of display images.
Based on the above, the pixel structures 100 may further include a shading layer (not shown) located above the main slit 130, so as to eliminate the color washout and the color shift of display images. However, the design of shading layer limits the display aperture ratio of the pixel structures 100. Therefore, the above problems needs to be overcome while maintaining the display aperture ratio and the wide viewing angle display effect in the wide viewing angle LCD panel.